THIS INVENTION relates to electrical circuit assemblies, and in particular to electrical circuit assemblies each comprising a plurality of stacks on a common, at least generally, planar support, each constituent stack having a plurality of at least substantially identically constructed modules, each such module including an, at least substantially, planar substrate, extending at right angles to the longitudinal axis of symmetry of the associated stack, the assembly having circuit elements mounted on at least one major surface of each substrate, and electrical interconnections are provided between the constituent modules of each stack, and between each constituent stack, to complete a required circuit. The circuit elements on any substrate may include conductors interconnecting circuit elements comprising components, such as packaged, or unencapsulated, semiconductor devices, also provided on the substrates.
The constituent stacks of such an electrical circuit assembly may be secured to the associated common support in any convenient way.
The constituent modules of each stack may be secured, in their desired locations within the stack, in any convenient way. Usually, a plurality of members are provided, extending parallel to the longitudinal axis of symmetry of the stack, and, at least partially, holding the modules in their required locations within the stack, each substrate co-operating with the members in any convenient way. Additional securing means, of any convenient form, may be provided for the stack. In any such arrangement, the provision of the members is advantageous, the members being capable of readily holding the modules in their required locations in the stack, during the assembling of the stack.
It may be desirable that faulty modules are readily replaceable, and, in particular, that the modules are resiliently held by the members within the associated stack.
Further, the electrical interconnections provided between the modules within each constituent stack may have any convenient form, and may comprise, at least some of, the members, at least partially, holding the modules in their required locations in the stack. Hence, the electrical interconnections may comprise, at least part of, the means securing the modules in the stack.
Terminals may be provided for each constituent stack of the electrical circuit assembly in any convenient way, and may comprise constituent circuit elements on at least one major surface of at least one substrate, and/or end portions of electrical interconnections provided between the modules, and comprising members, at least partially, holding the modules in their required locations in the stack.
In complex electrical circuit assemblies, having densely packed modules, and/or circuit elements on the modules, it is a problem to remove generated heat, before such heat can cause damage to the electrical circuit assemblies. Usually the heat is generated by some of the constituent components of the electrical circuit assemblies, but possibly, and conveniently, the heat is removed from adjacent circuit elements, such as conductors connected thereto; and/or from the substrates, when the substrates are of a material with a high coefficient of thermal conduction, the substrates possibly comprising heat sinks, with the circuit elements mounted thereon.